Objectives The role of consumers in healthcare services has been extended alongside rapid improvements in medical technology and availability of health information. One increasingly important manifestation of such changes is direct-to-consumer genetic testing (DTC-GT). Although DTC-GT is becoming widely available in South Korea in recent years, which is propelled by commercial business exploiting loopholes in government regulations, its potential implications for consumer’s health and well-being are poorly investigated. One of the main concerns with DTC-GT is that its consumers may often unable to interpret their test results correctly, given the very nature of direct-to-consumer information flow (i.e., lack of professional consultation) as well as various presentation formats. Compounding this issue further is the fact that presentation format can have substantial effects on risk perception and behavioral intentions. The current study examined how presentation formats adopted in DTC-GT results influence consumer’s perceived risks and their behavioral intentions. We used an experimental study design that closely reflects real-world DTC-GT results from commercial products currently available in the South Korean market.

Methods A web-based online survey was conducted in May and June 2022, with a sample of 720 South Korean adults randomized into three groups with different formats presenting the same magnitude of underlying risk: relative risk with line graphs (RR), absolute risk difference with line graphs (line ARD), and absolute risk difference with icons (icon ARD). The test results were designed based on actual test results from DTC-GT companies approved by the South Korean government. For each format group, either higher- or lower-risk condition of four disease items (diabetes, high blood pressure, insomnia, and lung cancer) were presented in a random order. Participants were asked to rate perceived risk and intention to change their behavior with 7-point Likert scales (1: very low - 7: very high).

Results Overall, the RR group showed the highest mean ratings in the higher-risk condition (RR 5.1, line ARD 4.9, icon ARD 4.9) and the lowest mean ratings in the lower-risk condition (RR 3.3, line ARD 3.3, icon ARD 3.5). Specifically, the mean ratings of perceived risk of getting lung cancer in the higher-risk condition was 5.0 in RR, higher than 4.7 in line ARD and 4.6 in icon ARD. On the contrary, the mean ratings of perceived risk of getting insomnia in the lower-risk condition was 2.8 in RR, lower than 3.1 in line ARD and 3.2 in icon ARD. Differences in behavioral intention were not visible by presentation format across the conditions.

Conclusions Among our sample of South Korean adults, perceived risk of getting disease varied by presentation format of DTC-GT despite their equivalent magnitude of risk. Compared with ARD formats, the RR format tends to lead to more exaggerated perceived risks for both higher and lower-risk conditions.